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Aturntable a is built into a stage for use in a theatrical production. it is observed during a rehearsal that a trunk b starts to slide on the turntable 10 s after the turntable begins to rotate. knowing that the trunk undergoes a constant tangential acceleration of 0.31 m/s2, determine the coefficient of static friction between the trunk and the turntable.

Give one example to show that when substances are mixed, it may result in a chemical or a physical change depending on the conditions.

If two parallel light rays hit a mirror, they will not be parallel to each other after they reflect.